#include<stdio.h>
#define SQUARES 64
int main(void)
{
    const double CROP = 2E64;
    double current, total;
    int count = 1;
    printf("square    grains     total     ");
    printf("fraction of \n");
    printf("          added       grains    ");
    printf("world total\n");
    total = current = 1.0;
    printf("%4d %13.2e %12.2e %12.2e\n",count,current,total,total/CROP);
    while (count < SQUARES)
    {
        count = count + 1;
        current = 2.0*current;
        total=total+current;
        printf("%4d %13.2e %12.2e %12.2e\n",count,current,total,total/CROP);
    }
    printf("That's all.\n");
}